The on-grid PV system converts solar radiation into electricity and feeds power into the grid (typically the public electricity grid) by a maximum power point tracking (MPPT), grid-controlled inverter.
In a grid-connected PV system, PV modules are wired together to form a PV array, the inverter inverts DC electricity into AC power. If the AC power is more than the owner's needs, the inverter sends the surplus to the utility grid for use by others. The utility provides AC power to the owner at night and during times when the owner's requirements exceed the capability of the PV system. Featured with no battery requirement and maintenance free, the grid-connected PV power offers consumers both economic and environmental advantages. This design will be a big development in the future.
The general principle is keeping the basic frame of the original circuitry. Therefore, we should embed the solar power system into the original circuitry with a low voltage switch box.
Considering the security and reliability of this grid connected system, we should add DC distribution boxes at the input port of inverters; the output of grid-connected inverter is three-phase four-wire system
Considering the security and reliability of this grid connected system, we should add DC distribution boxes at the input port of inverters; the output of grid-connected inverter is three-phase four-wire system
Main parts as follow:
PV array: Including solar panels, brackets, bases, combiner boxes, cables, etc.
DC-AC inverters: Including DC distribution boxes, inverters, etc.
Step-up equipments:
Including step-up transformer, distribution vacuum circuit breaker, high-voltage lightning arrester
Team Controller:
Including controllers, data processing/displaying system ,remote information exchange and control facilities
Accessorial Facilities:
Including lightning protection module.
The information below will be required for the design of Solar Power System:
1. Where will the solar power system be installed? The solar radiation in this area.
1. Where will the solar power system be installed? The solar radiation in this area.
2. How many KWH need the system to provide per day?
3. What about the Max load of the solar power system?
4. What is the output voltage, DC or AC?
5. What about the backup rainy days for the solar power system?
4. What is the output voltage, DC or AC?
5. What about the backup rainy days for the solar power system?
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Design case of solar on-grid pv system
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Item
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Name
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Spec.
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Quantity
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Remark
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1
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Solar panel
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180W
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56pcs
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8 pcs in series and 7 lines in parallel
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2
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Bracket and cable
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7sets
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3
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On-grid inverter
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10KW
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1pc
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Three-phase four wire grid connected type
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4
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Connection box
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2pcs
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5
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Lightning arrester
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2sets
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Height of lightning rod: 15m
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6
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Distribution room
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4-6㎡
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Or use existing distribution room
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